What is “lazy” colon or colonic inertia?
Colonic inertia is also known as a “lazy” colon or slow transit constipation. The colon is a muscular organ which plays an important role in the absorption of water and some electrolytes, storing stool, and propelling feces towards the rectum. It has its own nervous system as well as being innervated by the spinal cord. When the colon function is slow it is called colonic inertia. It is characterized by very infrequent bowel movements. The diagnosis is based on an x-ray exam known as a transit study. This test is performed by having the patient ingest a capsule which contains 20 markers (which will show up on x-ray) on each of three days. In the days preceding and during the study, patients need to be off any laxatives. An x-ray is then taken on day four (or whatever the protocol for a given hospital) in order to follow the transit of markers through the colon. A high number of markers left in the colon at the time of x-ray is an abnormal test and helps to establish the diagnosis. The
